"Aerially, we have to be very confident and Roger will be a great help in that area.

"See how many goals Negredo scores with his head, Kompany, Yaya Toure..."

Johnson will provide cover for a back four which has been without injured trio James Collins, Winston Reid and James Tomkins recently.

Allardyce will field a much stronger side than the one thrashed 5-0 at Nottingham Forest in the FA Cup on Sunday and he said: "I could easily have played a full-strength side but we have to have the freshest team possible against City so we can try to get to the cup final."